A practical reference on neurotrophic factor: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-04-19 and is reviewed periodically as new material appears.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
Identity and purity are commonly assessed by reversed-phase high-performance liquid chromatography, with ultraviolet detection near 214 nanometers for the peptide backbone. Mass spectrometry, either electrospray or matrix-assisted laser desorption, confirms molecular mass and detects truncation or modification products. Amino acid analysis can verify composition. Because the sequence contains no strongly absorbing aromatic residue apart from phenylalanine, detection wavelengths are chosen carefully. Purity values above 95 percent are typical for research-grade material.
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
Immunohematology is a branch of hematology and transfusion medicine which studies antigen-antibody reactions and analogous phenomena as they relate to the pathogenesis and clinical manifestations of blood disorders. A person employed in this field is referred to as an immunohematologist or colloquially as a blood banker. Their day-to-day duties include blood typing, cross-matching and antibody identification.
Russia is pursuing deals to supply its vaccine abroad. According to the Russian Direct Investment Fund, they had received orders for more than 1.2 billion doses of the vaccine as of December 2020. Over 50 countries had made requests for doses, with supplies for the global market being produced by partners in India, Brazil, China, South Korea, Hungary, and other countries. In August 2020, according to the Russian authorities, there were at least 20 countries that wanted to obtain the vaccine. The Israeli Hadassah Medical Center signed a commercial memorandum of understanding to obtain 1.5–3 million doses. Argentina agreed to buy 25 million doses of Russia's COVID-19 vaccine, subject to its clearing clinical trials; the vaccine was registered and approved in Argentina in late December 2020. The Brazilian state of Bahia signed an agreement to conduct Phase III clinical trials of the Sputnik V vaccine and planned to buy 50 million doses to market in northeastern Brazil. On 21 January 2021, Argentine president Alberto Fernández became the first Latin American leader to be inoculated with Sputnik V, shortly after it was approved for use in the country. Two months after being vaccinated he developed fever and headache, and tested positive for COVID-19. He was asymptomatic ten days later, was discharged from medical treatment subject to medical follow-up as usual for former COVID-19 patients, and resumed his normal activities.
== Capital crimes == In addition to the Penal Code, there are four Acts of Parliament that prescribe death as punishment for offences. According to the Think Centre, a Singaporean civil rights group, 70% of hangings are for drug-related offences. All eight hangings in 2017 were for drug-related offences that year, and 11 of 13 hangings in 2018 were also for drug-related offences.
An exudate is a fluid released by an organism through pores or a wound, a process known as exuding or exudation. Exudate is derived from exude 'to ooze' from Latin exsūdāre 'to (ooze out) sweat' (ex- 'out' and sūdāre 'to sweat').
Sources: en.wikipedia.org
During his second presidency, Donald Trump launched a campaign of anti-LGBTQ+ and especially anti-transgender policies that eliminated federal recognition of transgender people, stripped legal protections, and sought to erase trans identities from public life. Through a series of executive orders, the administration defined sex strictly by birth biology, banned trans people from the military, restricted or defunded gender-affirming healthcare, censored research and education materials, and targeted schools, universities, and cultural institutions accused of promoting "gender ideology". Additional measures barred transgender athletes from sports, limited passport access, and fueled international efforts to undermine trans rights. Accompanied by rhetoric portraying transgender people as a societal threat, these policies triggered widespread legal challenges, condemnation from human rights groups, and a surge in emigration and asylum claims by transgender Americans.
==== GSK–Novartis consumer healthcare buy-out ==== In March 2018, GSK announced that it has reached an agreement with Novartis to acquire Novartis's 36.5% stake in their Consumer Healthcare Joint Venture for US$13 billion (£9.2 billion).
== Taiwan Society for Mass Spectrometry == The major awards of the Taiwan Society for Mass Spectrometry include the Taiwan Society for Mass Spectrometry Medal and the Outstanding Scholar Research Award.
=== Example: Omalizumab Therapy === Omalizumab is a humanized monoclonal antibody for the treatment of various allergic diseases, including asthma, urticaria, and allergic rhinitis. It targets the immunoglobulin E (IgE) in human body, which plays an important role in allergic reactions. The efficacy of omalizumab may vary among patients. To identify responders to omalizumab, the level of several biomarkers can be measured, including serum eosinophils, fractional exhaled nitric oxide, and serum IgE. For instance, patients with higher baseline eosinophil counts are likely to respond better to omalizumab therapy.
As a consequence of the exchange rate policy, the bank must always adjust its interest rates to ensure a stable exchange rate and consequently cannot at the same time conduct monetary policy to stabilize e.g. domestic inflation or unemployment rates. This makes the conduct of stabilization policy fundamentally different from the situation in Denmark's neighbouring countries like Norway, Sweden, Poland and the United Kingdom, in which the central banks have a central stabilizing role. Denmark is presently the only OECD member country maintaining an independent currency with a fixed exchange rate. Consequently, the Danish krone is the only currency in the European Exchange Rate Mechanism II (ERM II), before Bulgaria and Croatia joined in 2020 (the latter uses the euro since 2023) In the first months of 2015, Denmark experienced the largest pressure against the fixed exchange rate for many years because of very large capital inflows, causing a tendency for the Danish krone to appreciate. Danmarks Nationalbank reacted in various ways, chiefly by lowering its interest rates to record low levels. On 6 February 2015 the certificates of deposit rate, one of the four official Danish central bank rates, was lowered to −0.75%. In January 2016 the rate was raised to −0.65%, at which level it has been maintained since then. Inflation in Denmark as measured by the official consumer price index of Statistics Denmark was 1.1% in 2017. Inflation has generally been low and stable for the last decades.
Sources: en.wikipedia.org
Purinergic receptors, also known as purinoceptors, are a family of plasma membrane molecules that are found in almost all mammalian tissues. Within the field of purinergic signalling, these receptors have been implicated in learning and memory, locomotor and feeding behavior, and sleep. More specifically, they are involved in several cellular functions, including proliferation and migration of neural stem cells, vascular reactivity, apoptosis and cytokine secretion. These functions have not been well characterized and the effect of the extracellular microenvironment on their function is also poorly understood. Geoffrey Burnstock originally separated purinoceptors into P1 adenosine receptors and P2 nucleotide (ATP, ADP) receptors. P2 receptors were later subdivided into P2X, P2Y, P2T, and P2Z receptors. Subclasses X and Y mediated vasoconstriction and vasodilation, respectively, in the smooth muscle of some arteries. They had been observed in blood vessels, smooth muscle, heart, hepatocytes, and parotid acinar cells. Subclass T was only observed in thrombocytes, platelets and megakaryocytes. Subclass Z required ~100 μM-ATP for activation, where the previous classes required <1 μM. They had been observed in mast cells and lymphocytes. In the early 1990s, purinoceptors were cloned and characterized, and the P2 subclasses were redefined. Now, P2 receptors are classified based on structure: P2X are ionotropic and P2Y are metabotropic. Appropriately, P2Z was reclassified as P2X7 and P2T was reclassified as P2Y1.
=== Dental appliances === Mandibular advancement splints (mandibular advancement devices) are designed to hold the lower jaw slightly down and forward relative to the natural, relaxed position. This position keeps the tongue farther away from the back of the airway and may be enough to relieve apnea or improve breathing. This device is a mouthguard similar to those used in sports to protect the teeth. Mandibular advancement splints are used for snoring and for mild to moderate obstructive sleep apnea. They are most suitable for people with AHI < 25, BMI < 30, and good dentition. Where appropriate, they are considered a good therapy choice as they are non-invasive, easily reversible, and quiet. They are generally well-tolerated because they are less uncomfortable. However, they may not be as effective as CPAP. Oral devices have been shown to treat OSA successfully. These include the polysomnographic indexes of OSA, subjective and objective measures of sleepiness, blood pressure, aspects of neuropsychological functioning, and quality of life. The focus of improvement in appliance design is in reducing bulk, permitting free jaw movement (i.e., yawning, speaking, and drinking), and allowing the user to breathe through their mouth (early "welded gum shield"-type devices prevented oral breathing). Tongue repositioning (retaining) devices are made of soft acrylic and cover the upper and lower teeth, creating a seal with the lips. They have a "bulb" or "bubble" which sticks out of the front of the mouth.
==== Discontinuation ==== If lithium is stopped suddenly, there is a 50% risk of sudden mania within one month of stopping. In the first year after discontinuation of lithium, there is up to a 20-fold increase in the rate of suicide or attempted suicide compared to lithium maintenance. If discontinuing lithium, it is recommended to taper it gradually and in a controlled fashion. Gradual tapering has been shown to lower the risk of relapse and suicidal events. In patients gradually tapering off the medication, discontinuation symptoms including irritability or restlessness, and somatic symptoms like vertigo, dizziness, or lightheadedness may occur. Discontinuation symptoms are generally mild and self-limiting within weeks.
=== Blue Men of Lurgan === The "blue men of Lurgan" were a pair of Lurgan men suffering from what was described as "familial idiopathic methemoglobinemia" who were treated by James Deeny in 1942. Deeny, who would later become the Chief Medical Officer of the Republic of Ireland, prescribed a course of ascorbic acid and sodium bicarbonate. In case one, by the eighth day of treatments, there was a marked change in appearance, and by the twelfth day of treatment, the patient's complexion was normal. In case two, the patient's complexion reached normality over a month-long duration of treatment.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
Solid peptide is best kept frozen at about minus 20 degrees Celsius in a sealed container with desiccant. It should be allowed to reach room temperature before opening to prevent condensation. Repeated warming and cooling of the same vial is discouraged.